We plough the fields and scat-ter the good seed on the land... la la la. Yes it's Harvest Festival season so grab yer produce and head off to the local village hall for a slap up Harvest Supper with all the trimmings. But talking of good seed - it's Seed Gathering Season so don't forget to gather as you go and here are some events in your area to help you.

The line-up this week:

1. Planet Pick of the Week – Hands On Real Science
2. Gimme Five – facts about seeds
3. Stump the Scientist – How much does a hole weigh?
4. Activity of the Week – Amazing onions
5. Mouses at the Ready – Flipside magazines
6. Noticeboard – FYI
7. Recommended websites of the week
8. The Winners’ Enclosure
9. Joke of the Week

Are you looking for inspiration? Want to give your science lessons that X-factor? Well how about spending your coffee break browsing the Hands On Real Science section? This is a big round up of ways that real school students, young and old, have contributed something to real scientific knowledge. So have a look at the projects on offer and you may find something that's right up your street - not to mention info about possible funding/partnership opportunities.

Happy browsing...

Seeds

1. The largest seed in the world is the double coconut. It can measure up to 50cm (1.6ft) around the middle! Coconuts have a fibrous coating and an air space inside them, because they need to be able to float to a new home. Some coconuts have floated 2,000km over the sea before they find dry land!
2. Some orchid seed-pods hold 3 million seeds.
3. Some seeds found in frozen soil in Canada were grown and produced flowers - the seeds were thought to be more than 10,000 years old!
4. There are some very dangerous seeds, such as those that come from deadly nightshade; two berries could kill you. Even more dangerous are the seeds from the Castor-oil plant - one bean will kill an adult.
5. Most oak trees don't grow acorns until they are at least 50 years old. If you have planted an acorn, how old will you be before you can plant its acorns?

These facts were taken from information about seeds

Remember last week when Ryan of Year 6 asked...

“Does light weigh anything? Because it can be sucked in by black holes?”

Well Mr Photon soon chipped in

“Dear Ryan You may remember being taught that light travels in straight lines? In fact Albert Einstein discovered that light simply follows the shape of space (he actually says space-time). Space-time near a black hole is very very steeply curved. A light beam coming near to a Black hole will travel into it. There is no 'sucking in' like a vacuum cleaner. Very interestingly physicists realised there is an area near the ‘edge' of a Black hole where light beams will travel forever around it in a circle. This is the 'Event Horizon' that you may have heard about.”

Well that might solve the ‘sucking in' aspect and also helps Hugh Mackay (aged 8) who remarked “I saw a picture in the newspaper about stars being born in a black hole. The thing that's puzzling me is how could stars be born in a black hole? Surely they would be sucked back in! “ James Stevenson suggested a good source of information on this topic and if you'd like more details then email us with BLACK HOLE in the subject line to planet-science.news@nesta.org.uk However Sharon Colpman addresses the matter of whether light weighs anything and it is truly a magnificent feat of mathematics. Lead on Sharon...

“Sunlight, composed of photons of various energies, has MOMENTUM but no MASS. That is, it does not "weigh" anything in the usual sense that we use the term "weigh" because the earth's gravitational field has almost no effect upon photons. They are not attracted by the force of gravity. When we "weigh" some object that has a certain mass, we measure the force that the earth exerts upon that mass. The mass comes to rest on our balance or scales, and hence has a "rest mass". Since photons, at least from the Sun, always travel at the speed of light they can have no "rest mass". However, they can and do exert a force, e.g. solar "winds".

Since sunlight has energy, it also has a mass associated with it as indicated by Einstein's famous equation E = mc^2 or m = E/(c^2). The sun converts 4.2 x 10^9 kg of mass to energy every second. Using this number, we can estimate the amount of energy (mass) from the sun hitting the earth by calculating the fraction of the entire solid angle the earth intercepts as seen by the sun. Since the diameter of the earth is about 1.3 x 10^7 m and it is 1.5 x 10^11 m from the sun, it subtends an angle of about 8.7 x 10^-5 radians. If we square this angle and divide by 4 pi = 12.6, we get the solid angle fraction subtended by the earth, which I calculate to be about 6 x 10^-10 of the entire solid angle. Multiplying this by the 4.2 x 10^9 kg burned by the sun every second and we obtain 2.5 kg/s as the mass of the photons (light) from the sun striking the earth every second.”

Wow! Thanks scientists one and all, on this occasion the scientist was NOT stumped!

If you can help or have a burning question of your own then send us an email with STUMP THE SCIENTIST in the subject line to planet-science.news@nesta.org.uk

A-maze-ing onions

Onions may not be quite as cute and cuddly as hamsters, but you can still teach them to find their way through a maze!

You will need:

1. An onion (ideally already sprouting)
2. A shoe box
3. Another spare cardboard box
4. Strong scissors
5. Sticky tape

What you do:

1. First build a maze for your onion!
2. Use your spare cardboard box to cut rectangles about the same size as the smaller side of the shoe box. These will be the dividers inside your maze. You need at least two but you could make more if you like.
3. For each divider, cut a ‘window' in the cardboard about 3 cm square. It will make the maze more interesting if they are in different positions on each divider.
4. Cut an ‘exit' door for the onion shoot at one end of the shoe box.
5. Put the onion at the other end of the shoe box.
6. Fit the dividers into the box, spacing them out between the onion and the exit. Try to put them in so the onion will have to change direction to get through each hole.
7. Try to find a sunny place to leave it (so the sun can shine on the exit) but where it won't be disturbed.
8. Leave for about 3 weeks and then check to see how it's getting on.

What's going on?

The sprouts on your onion should have started to find their way out of the maze. They are growing towards the light coming through the exit. Biologists call this phototropism. You might have noticed this already with indoor plants. They grow towards the light, and can get very lopsided unless you turn their pots round occasionally.

So how does the onion ‘know' where the light is, and how does it grow towards it? The tips of plant shoots contain a growth hormone called an auxin, which makes the shoot grow faster. But light destroys the auxin, so it only works on the side that doesn't have any light. The side without any light grows longer and the shoot ends up bending towards the light.

You might have also noticed that plants without much light grow long and spindly. This is because there is lots of auxin in the plant and it grows fast - but the plant won't be very healthy because it needs light to make food for itself by photosynthesis.

More ideas:

Try seeing if a sprouting potato can find its way through the maze. Have a race between the potato and the onion to see which shoots grow quicker.

You could grow plants from identical seeds, one in the dark and one in the light to compare them. Look especially at the colour of the leaves. (See also our Light Fantastic experiment.)

Think of ways to test whether the auxin is only in the tips of the shoots or all along the shoots.

This activity came from the Tim Hunkin, except he used potatoes instead of onions. You can see the ‘How to make a potato find its way through a maze' and lots more exciting experiments at Hunkin's Experiments.

This week we have TEN two-packs of Flipside magazine to give away. The October edition plus another. So if you want to read more about the top inventions of the next 50 years or discover the world's most poisonous food then you know what to do...

Email us with your name and address, and the words ‘OCTO FLIP' in the subject line, to planet-science.news@nesta.org.uk.

The draw will take place at 5pm on Wednesday 15 October.

The Great Plant Hunt is a primary school science resource inspired by a year of celebrations to mark the 200th birthday of Charles Darwin. The Royal Botanic Gardens, Kew (RBG Kew), will be sending primary schools free resources in March 2009. Every state primary school in the UK will be sent a Darwin Treasure Chest jam-packed with outstanding free resources. The fun activities - which take place in the classroom, online and in the great outdoors - include exploring habitats, collecting seeds and growing plants. And you can have a sneaky peek at the type of activities available for each year group ahead of receiving the resource.

Best of all, your school will be helping out with real scientific experiments. The information and seeds your pupils gather will be sent to researchers at Kew's Millennium Seed Bank, who are working to collect and protect seeds from thousands of plants worldwide.

By the way, if you've got a good website to recommend then send it along to us at planet-science.news@nesta.org.uk with RWW in the subject line.

Thank you very gladly.